New colouring process



United States Patent O NEW COLOURING PROCESS Timothy Leslie Dawson,Manchester, England, assignor to Imperial Chemical Industries Limited,London, England, a corporation of Great Britain N Drawing. Filed Jan.10, 1957, Ser. No. 633,387

Claims. (Cl. 8-31) This invention relates to a new colouring process,and more particularly it relates to a new colouring process suitable forthe application of basic dyestufis and dyestuffs containing ternary orquaternary salt groups.

These latter dyestulfs may be applied to textile materials byconventional dyeing methods and then rendered insoluble by treatment ofthe dyed textile material with alkali to give dyeings having good lightand wash-fastness. When applied in this way the aflinities of thedyestufis for cellulosic materials are not entirely satisfactory anddeep shades are not readily obtainable. It is known that deep shades arereadily obtainable on cellulosic materials by impregnating with thedye-liquor and then dry ing before treating with alkali, but this methodsutfers from the defect that the dyestutf shows a tendency to migratewhile the textile material is being dried and the final dyeings areuneven.

It has now been found that the afiinity of cellulosic two tiles, andmore particularly of cotton and cuprammonium rayon textile materials forthe above dyestulfs may be greatly increased by impregnating the saidtextile materials with a mixture of polyacrylic acid and an alkali metalsalt of polyacrylic acid.

According to the invention, therefore, there is provided a process forcolouring cellulosic textile material which comprises impregnating thesaid material with a mixture of a polymer of acrylic acid and one ormore alkali metal or ammonium salts of a polymer of acrylic acid,thereafter dyeing the said material with a basic dyestuff or a dyestuflcontaining ternary or quaternary salt groups, and finally treating thedyed material with alkali to complete the fixation of the dyestuff.

As examples of cellulosic textile materials which may be coloured by theprocess of the invention there may be mentioned cotton, linen,cuprammonium rayon, and viscose rayon.

As examples of alkali-metal salts of polymers of acrylic acid which maybe used in the process of the invention there may be mentioned sodiumand potassium salts of polymers of acrylic acid.

The impregnation of the said textile material may be convenientlycarried out by passing it through an aqueous solution containing both apolymer of acrylic acid and alkali or ammonium salt of the polymer andthen drying. The solution may conveniently be obtained either by partialneutralisation of a polymer of acrylic acid with ammonia or a suitablealkali-metal hydroxide, carbonate or bicorbonate, or by partialacidification of a solution of an alkali-metal or ammonium salt of apolymer of acrylic acid. The polymer of acrylic acid (or alkali-metal orammonium salt thereof) used may be obtained by any method known from theliterature or used in practice for the manufacture of polymers ofacrylic acid, for example by polymerisation of acrylic acid eithercatalytically or by heat, by polymerisation of acrylonitn'le followed byeither acid or alkaline hydrolysis and by polymerisation of esters ofacrylic acid, for example ethyl acrylate, followed by hydrolysis of thepolymer formed,

7 ice and such hydrolyses may be carried out on polymers either in thesolid state or in an emulsified state. The products so obtained aresubstantially polymers of acrylic acid (or salts thereof) but maycontain minor amounts of nitrile, amide or ester groups, depending onthe method of preparation. Similar polymers may be obtained, if desired,by the co-polymerisation of mixtures of acrylic acid with minor amountsof co-polymerisable substances containing amide, nitrile or estergroups.

The total amount of the polymer of acrylic acid and salt thereof presentin the solution may lie between 0.1 parts and 2.5 parts in each parts byweight of the solution, but it is preferred to use a solution containing0.2 to 0.5 parts in each 100 parts by weight of the solution.

Polymers of acrylic acid may be used which form solutions in 2 N sodiumhydroxide having viscosities at 20 C. of not less than 2 centipoises andnot more than 10 centipoises when 10 grams of the polymer are dissolvedin sufiicient 2 N aqueous sodium hydroxide to give a volume of 1 litre.*It is preferable, however, to use a polymer of acrylic acid which givessuch a solution in 2 N sodium hydroxide having a viscosity of not lessthan 2 and not more than 4 centipoises at 20 C.

The proportion of polymer of acrylic acid and salt thereof present inthe solution used for impregnation of the textile materials may be suchthat the pH of the solution is not less than 3 and not more than 10, butit is preferred to use a proportion such that the pH of the solution isnot less than 5.5 and not more than 6.5

Suitable dyestufis for use in the invention are for example thoseobtained by rcacting chloromethyl derivatives of phthalocyanines withtertiary amines or thioureas as described in United Kingdomspecification No. 587,636 and also dyestuffs obtained in a similarmanner from chloromethyl derivatives of anthraquinone vat dyestutfs, forexarnple dibenzanthrone and isodibenzanthrone, and from chloromethylderivatives of azo pigments, for example 4z4'di(6"-methylbenzthiazyl-)azobenzene. As examples of basic dyestuffswhich may be used, there may be mentioned Methylene Blue 2B5 (ColourIndex No. 922), Victoria Blue BS (Colour index No. 729), MagentaPNS(Colour Index No. 677) and Auramine OS (Colour Index No. 655).

It has been found that the coloured textile materials obtained by thenew process are considerably more resistant to removal of dyestufi bywet or dry abrasive treatments than are coloured textile materialsobtained when the pretreatment with polyacrylic acid and polyacrylate isomitted.

When a bath-dyeing technique is used, that is the material is dyed on awinch or jig, the dye-liquor exhausts to a higher degree, and deepershades are obtained than can be obtained on textile materials which havenot been treated with polyacrylic acid and polyacrylate.

When a pad-dry or pad-steam dyeing technique is used, the pretreatedtextile material gives dyeings having a better colour value. When apad-dry technique is used, dyestuff applied to pretreated textilematerials shows much less tendency to migrate under adverse dryingconditions.

The invention is illustrated but not limited by the following examplesin which the parts are by Weight.

Example 1 A solution is prepared by dissolving 0.5 parts of a polymer ofacrylic acid in 99.5 parts of water containing suificient sodiumhydroxide for the solution to have a pH of 5.7. Cotton limbric is passedthrough this solution and squeezed so as .to give an increase in weightof 100% over the weight of the cloth which is then dried at 100 C.

l'parts of "the pre-treated cotton limbrie are thoroughly rinsed inwater, then introduced into 5000 parts of dye-liquor containing 1.5parts of the dyestufl obtainedby reactingcoppertri-(chloromethyl-)phthalocyamine-with tetramethy-lthiourea. The dyebathis heated to the boiling pointiduring 30 minutes, and maintained at thistemperature for 30 minutes, with continual agitation of the fabric.During this time, the pH of the dyebath is maintained at 3.5 by theaddition ofacetic acid.

, f vThe cotton limbric is. then removed, rinsed in water and immersedfor minutes in a boiling solution containing 20 parts of sodiumcarbonate in 1000 parts of water, .It is thenboiledfor lOnninutes inasolution containingl part of a detergent obtained by condensing ethyleneoxide with an alkyl phenol in 1000' parts of water, thenrinsed withwater and'dried. h V V The uptake of dyestuif 'on' the. cotton limbric'when measured by spectrophotometric examination of the exhaust liquor isfound to be-1'.25 parts. 100 parts of cot ton limbric which had not beenpretreatedwhen dyed similarly given an uptake. of 0.6 parts of dyestuif.

. The polymer of acrylic acid usedin this example. is obtained bycatalytic polymerisation ofacrylic acid and forms a solution in 2 Nsodium hydroxide having a viscosity of 2.4 centipoises at 20C. when 10parts of f '7 r 7 2,955,900 1 I 4; Example 6 K 100 parts of cottonlimbric are pretreated as in Ex:- ample l and dyed, fixed and dried asdescribed therein but using only suflicient dyestufi' in the'dyebath togive an uptake of 0.5 parts of dyestuif. 100 parts of cotton limbricwhich has not been; pretreated are also dyed, fixed and dried to give anuptake of 0.5 part of dyestutr'. The pretreated cotton limbric has muchgreater resistance to removal of the dyestuff under dry and wetconditions than the cotton limbric which has not been pretreated. 7

Example 7 A mixture of 486'p'arts of water; and Spartsof a 5% aqueoussolutionofsulphurieacidds. heated to 40 C. and 2 parts of ammoniumpersulphate in 8'parts of water, 2 parts of sodium meta-bisulphiteinSparts of water. and 60 parts ofacrylonitrile are added. Immediate Ipolymerisation occurs and the temperature of the mixpolyacrylic acid aredissolved in sufficient 2 N sodium, 7

hydroxide to .give a total volume of .1' litre.

7 7 Example 2 100'parts 'oi cuprammonium rayon-sateen pretreated V anddyed as described for the cotton limbric in Example Cuprammonium V 1;The dyestuff uptakeis 1.48 parts. rayon sateen which is not pretreatedhas a'dyestutf up take of 0.6 parts.

-. j Example '3 The solution of polymer of acrylic acid used in Examplel to impregnate the cotton limbric is replaced by a solution of 1 partof polymer of acrylic acid in 99 parts of water, containing sufiicientsodium hydroxide to have a pH of 5.7, and the amount of dyestutf in thedyebath isincreased to 2.5 parts. A dye uptake of. 2.2 parts isobtained. V

Example 4 7 Cotton limbric is pretreated as described in Example 1.

The fabric is then passed through a solution containing 10 parts of the.dyestuiI described in Example 1 and 5 parts of acetic acid' in 1000parts of water and squeezed Example 1.

'When cotton limbric which has not been'pre-treated is dyed and'fixed inthe same way, more of the dyestufi is removed from the dyeing during thetreatment with g sodium carbonate solution than is removed from thepretreated cotton limbric and more is removed from the dyeingwhich hasnot been 'pre-treated when exposed to friction under wet or dryconditions than is removed from the pre-treated cotton limbric.

Example 5 ofthe dyestufi described in Example 1 and S pants of (glacialacetic, acid in 1000 parts of water.

The strips are thenseparately wound several round'a cylinder'land driedin a. stream of warm The dyestuif on the strips ofcotton limbric whichhavebeen pretreated show much'less tendency-to migrate to the?outer-layers of the cotton limbric than does'the dyestuif on theuntreated strips.

. water and then introduced into 5,000 parts of dye liquor thiourea.

Bothpre-treate'd and non-pretreated strips: of '.cotton limbric arepassed. through 'a solution containing 10 parts I ture rises to 68 C.,The temperatureis'adjusted to 60 C. and the mixture is maintained atthis temperature for one hour. 46 parts of sodium hydroxide are'added to.the polymer slurry and the. mixture is heated at 90-95 C. for 24 hours,the-volume of the'solution being kept constant during this time by theaddition of water.

Analytical estimation of the product indicates that thepo-lyac rylonitrile is parts hydrolysed to sodium POlyacrylate The polymer forms asolutionhaving" a viscosity of 3.5 centipoises at 20 C.' when )aquantity equivalent to 10 parts ofpolyacrylic acid'is dissolvedsuflicient 2 N sodium hydroxide to' givea total'volume of one litre. i pr The above polymer solution is diluted to give' a solution equivalentto 0.5 part of polyacrylic acid in 99.5 parts of water containingsuflicient ace tic acid for the solution toihave a pH of 5.7. Cottonlimbric is passed through this solution and squeezed so as to give anincrease in weight of 100% over {the weight of the cloth which is thendried at 100 C.

. 100 partsof the pretreated cotton limbric is rinsed in containing 1.5parts of the dyestufi'obtained by reacting coppertri(chloromethyl)phthalocyanine with 'tetramethyl- Thefdyebath is heatedto the boiling'point during 30 minutes and maintained at thistemperature for 30 minutes'with continual agitation of the fabric.During this time the pH of the dyebath is maintained at 3.5 by theaddition, of acetic acid. {The cotton limhric is; then removed, rinsedin water and immersed for 5 minutes in a boiling solution containing 20parts of 'sodium carhonatein 1000 parts of water. 'It is" then boiledfor 10 minutes in a' solutionfcontaining l part of a detergent obtainedby condensing ethylene oxide'with alkyl phenol in 1000 parts of water,rinsed with water, and driedq The uptake of dyestuff on the cottonlirnbric when measured by spectrophotometric examination of the exhaustliquor Example 8 mixture ofz500 parts of' water, 3.8 parts of sodiumcarbonate and 8-,parts of Turkey Red Oil' is heated to C. and stirredvigorously while simultaneously from 7 separate vessels, there are addedduring l /z hours 400 parts of ethyl acrylate monomer, 8 parts of TurkeyRed Oil in 200 parts of water, and l.32.parts o f ammonium persulfateinparts of water. Care is taken to main-;

tain therates of addition of monomer, catalyst and surface active agentconstant. .When'the additions are complete, the temperature of thedispersion ismaintained at Sj0-92?1 C. for. a further hour; to completethe polymerization a i V a 56 parts of sodium are dissolved 100 v partsof water and this solution is added to 500 parts of an aqueousdispersion of polyethyl acrylate prepared as described above. Themixture is stirredand heated to about 90 C. and maintained at 8090 for 3hours. Titration of the residual sodium hydroxide with standard acidsolution indicates that the polyethyl acrylate is 75% hydrolysed tosodium polyacrylate. V The polymer obtained forms a solution having aviscosity of 8.25 centipoises at 20 C. when a quantity equivalent toparts of polyacrylic acid is dissolved in suificient 2 N sodiumhydroxide to give a total volume of one litre.

The above polymer solution is diluted to give a solution equivalent to0.5 part of polyacrylic acid in 99.5 parts of water containingsufiicient acetic acid for the solution to have a pH of 5.7. 100 partsof cotton limbric is pretreated and dyed as described in Example 7 usingthe above solution for the pretreatment. The uptake of dyestuff is 1.09part per 100 parts of cotton limbric.

Example 9 A mixture of 350 parts of water, 2.5 parts of sodium hydroxideand 10 parts of Turkey Red Oil is heated to 90 C. and to this mixtureare added 750 parts of ethyl acrylate monomer, 100 parts of Turkey RedOil in 200 parts of water and 6.25 parts of ammonium persulphate in 200parts of water. Polymerisation is effected as described in Example 8.45.2 parts of sodium hydroxide are dissolved in 500 parts of water andthis solution is added to 200 parts of the aqueous dispersion ofpolyethyl acrylate prepared as described above. Hydrolysis is carriedout as described in Example 8 except that the total time of hydrolysisis 16 hours. Titration of the residual sodium hydroxide with standardacid solution indicates that the polyethyl acrylate is 95% hydrolyzed tosodium polyacrylate. The polymer obtained forms a solution having aviscosity of 2.04 centipoises at 20 C. when a quantity equivalent to 10parts of polyacrylic acid is dissolved in suflicient 2 N sodiumhydroxide to give a total volume of one litre. The above polymersolution is diluted to give a solution equivalent to 0.5 part ofpolyacrylic acid in 99.5 parts of water containing suflicient aceticacid for the solution to have a pH of 5.7. 100 parts of cotton limbricis pretreated and dyed as described in Example 7 using the abovesolution for the pretreatment. The uptake of dyestutf is 1.23 parts per100 parts of cotton limbric.

Example 10 A solution containing 80 parts of acrylic acid monomer in 20parts of water is refluxed at about 140 C. After 10 minutes polyacrylicacid begins to separate from the monomer solution. After heating for afurther 45 min utes the solid polymer is separated from the residualsolution and dried giving 75 parts of polyacrylic acid. The polymerforms a solution in 2 N sodium hydroxide having a viscosity of 2.0centipoises at 20 C. when 10 parts are dissolved in suficient 2 N sodiumhydroxide to give a total volume of one litre.

A solution of this product is prepared by dissolving 0.5 part in 99.5parts of water containing suflicient sodium hydroxide for the solutionto have a pH of 5.7. 100 parts of cotton limbric is pretreated and dyedas described in Example 7 using the above solution for the pretreatment.The dyestufi uptake is 1.03 part per 100 parts of cotton limbric.

Similar results are obtained if the polymer solution is adjusted to pH5.7 with either ammonium or potassium hydroxide in place of sodiumhydroxide.

Example 11 100 parts of cotton limbric is pretreated and dyed asdescribed in Example 7 except that the dyestufi is replaced by the dyeobtained by reacting chloromethyl-4:4-di(6"-methylbenzthiazyl)-azobenzene with tetramethylthiourea. The dyestufiuptake is 1.25 parts per 100 parts of cotton limbric. 100 parts ofcotton limbric which has not been pretreated when dyed similarly givesan uptake of 0.6 parts of dyestuff.

Example 12 100 parts of cotton limbric is pretreated and dyed asdescribed in Example 7 except that the dyestutf is admixed with an equalweight of the dyestutf used in Example 11. The uptake of the greendyestufi' mixture is 1.31 parts per 100 parts of cotton limbric. 100parts of cotton limbric which has not been pretreated when dyedsimilarly gives an uptake of 0.6 parts of dyestufr'.

Example 13 100 parts of cuprammonium rayon sateen is pretreated and dyedas described for the cotton limbric in Example 7. The dyestutf uptake is1.48 parts. Cuprammonium rayon sateen which is not pretreated has adyestufi uptake of 0.6 part per 100 parts of cuprammonium rayon sateen.

Example 14 100 parts of cotton limbric is pretreated and dyed asdescribed in Example 7 except that the concentration of the polymersolution is increased until equivalent to 1 part of polyacrylic acid in99 parts of Water containing sufiicieut acetic acid for the solution tohave a pH of 5.7. The amount of dyestufi in the dyebath is increased to2.5 parts. 'A dye uptake of 2.2 parts per 100 parts 'of cotton limbricis obtained.

Example 15 Cotton limbric is pretreated as described in Example 7. Thefabric is then passed through a solution containing 10 parts of thedyestulf described in Example 7 and 5 parts of acetic acid in 1,000parts of Water and squeezed so as to give an increase in weight of overthe weight of the cloth, which is then dried at C. and passed through aboiling solution of sodium carbonate in 100 parts of water. It is thentreated with detergent as described in Example 7.

When cotton limbric which has not been pretreated is dyed and fixed inthe same way, more of the dyestufi is removed from the dyeing during thetreatment with g sodium carbonate solution than is removed from thepretreated cotton limbric, and more is removed from the dyeing which hasnot been pretreated when exposed to fric tion under wet or dryconditions than is removed from the pretreated cotton limbric.

Example 16 100 parts of cotton limbric is pretreated as described inExample 7 and dyed, fixed and dried as described therein but using onlysuficient dyestufi" in the dyebath to give an uptake of 0.5 part ofdyestutf. 100 parts of cotton limbric which have not been pretreated isalso dyed, fixed and dried to give an uptake of 0.5 part of dyestutf.The pretreated cotton limbric has much greater resistance to removal ofthe dyestuff by abrasion under dry and wet conditions than the cottonlimbric which has not been pretreated.

Example 18 100 parts of cotton limbric is pretreated as described inExample 7. The fabric is then introduced into 5000 parts of dye liquorcontaining 0.5 part of Victoria Blue 7 BS (Colour Index No. 729),and.2.5 parts of glacial aceticacid. The dyebath is heated to 70 C.during 39 minutes and maintained at this temperature for 30 minutes,with continual agitation of the fabric. 7

Thecotton li'mbric is then removed, rinsedwell in water and dried. Theuptake of dyestufi on the cotton limbric when measured'byspectrophotometric examination of the exhaust liquor is found to be 0.4parts per 1 parts of cotton lirnbric. 100 parts of cotton limbric whichhas not been pretreated similarly gives an uptake of 0.21 parts ofdyestuff. p a

V 7 Example 19 100parts of cotton limbric is pretreated as described inExample 7. The fabric is then introduced into 5,000

parts-of'dye liquor containing 0.5 part of Methylene Blue 2B8 (ColourIndex No; 922) and 2.5 parts ofj'glacial acetio acidr The dyebathisheated to 70 C. during 30 minutes and maintained at thisitemperature for30minutes with continual agitation of the fabric. The cotton lirnbric isthen removed, rinsed Well in Water. and dried.

The uptake 'of dyestufl'on the cotton limbric is found to be 0.36partper 100 parts of cotton limbricf 100 parts of cotton limbric whichhas not been pretreated when dyed similarlygives an uptake of Olpart ofdyestufi; ;WhatI.clairn is; v e

1. Process forcolouring solution of a mixture of a polymer of acrylicacid and at least one salt of the group consisting of alkali metal andammonium salts of a'polyrner of acrylic acid, thereafter dyeing thematerial .With a dyestuff selected from'thetclass. consistingof'dyestuffs containing ternary'salt groups and.

dyestufiscontaining quaternary salt groups; which are rendered insolublein 'Water by alkali, and finally-treat ation of the dy'estuff.

ingthe dyed'material with alkali to complete: the fix- 12. Process .forcolouring. cellulose-textile material as claimed in claim- 1 wherein thealkali-metal salts ofpolymers ofacrylic acid are selected from the groupconsisting of the sodium and potassium salts.

3.: Process rd; colouring cellulose textile materialias"*claimedinjclaim 1 wherein said polymer of acrylic acid.

is one which forms a solution in 2 N sodium hydroxide having a viscosityat 20 C. of not less thaln2 centipoises V celliflose textile materialwhich. comprises impregnating the said material'with an aqueous and notmore than 1'0 centipoises, whenilt) grams ofthe material prior to the'dyeing step polymer. are. dissolved inrsufiicient 2 N aqueous sodiumhydroxide to give-a volumeof llitre.

41 Process. for' colouring. cellulose .textileQmatetial; as claimedinclaim 1 wherein. the proportion ofpolymer of acrylic acid and saltthereof presentin the 'solutionvused for imp'regriationof the textilematerials is 'suchthat the pHof the solution is not less than 3 and notmorethan 10. a I

' 5. Process for colouring cellulose textile material as claimed inclaim .1 wherein said polymer of acrylic acid is one which forms asolution in 2 N sodium hydroxide having'aviscosity at 20 C., ofnot lessthan 2 centipoises and not more than 4 centipoises when 10 grams'of thepolymer are dissolved'in suflicient 2 N aqueous sodium 5 aqueoussolution containing both said polymer of acrylic 2 acid and salt'thereofand then drying the impregnated '8 Process for colouring. cellulosetextile material as claimed-in clain1- 7 wherein the total amounto fthepolymer'of acrylic acid and salt thereof present in the solunan-rebetween 0.1 part and 2.5parts in each. IOQ parts hy weightof thesolution. 5

i 9 Process for colouring cellulos' e textile materiai as claimed inclaim 7 wherein the total amount of thepoly mer ofacrylic acid and saltthereof present in: the solution is between 0.2 to 0'.5 pa rt by Weightof the solution.

1( Cellulose textile materials whenever coloured by a process asdefinedin claim 1. Y

. References. Cited in the file of this patent UNITED STATES PATENTS:

2,215,196 7 Schlack Sept; 17, 2,343,095 Smith' Feb.29,1944 2,764,570Kowolik Sept. 25, 1956 FOREIGN PATENTS 1 7 433,210 Great Britain 'Aug.'9; i935

1. PROCESS FOR COLOURING CELLULOSE TEXTILE MATERIAL WHICH COMPRISESIMPREGNATING THE SAID MATERIAL WITH AN AQUEOUS SOLUTION OF A MIXTURE OFA POLYMER OF ACRYLIC ACID AND AT LEAST ONE SALT OF THE GROUP CONSITINGOF ALKALI METAL AND AMMONUIM SALTS OF A POLYMER OF ACRYLIC ACID,THEREAFTER DYEING THE MATERIAL WITH A DYESTUFF SELECTED FROM THE CLASSCONSISTING OF DYESTUFFS CONTAINING TERNARY SALT GROUPS AND DYESTUFFSCONTAINING QUATENARY SALTGROUPS, WHICH ARE RENDERED INSOULBLE IN WATERBY ALKALI, AND FINALLY TREATING THE DYED MATERIAL WITH ALKALI TOCOMPLETE THE FIXATION OF THE DYESTUFF.